Improvement in means for operating car-brakes



2Sheets--Shet2. J. Y. SMITH.

Improvement ih Means for Operating Car-Brakes.

No.130,323. Patented Aug. 6,1872.

UNITED STATES PATENT OFFICE.

JOHN Y. SMITH, or rIrTsBuRe, PENNSYLVANIA.

IMPROVEMENT IN MEANS FOR OPERATING CAR-BRAKES.

Specification forming part of Letters Patent No. 130,323, dated August6, 1872.

Specification describing an Improvement in Vacuum-Brakes for RailwayCars, invented by JOHN Y. SMITH, of Pittsburg, in the county ofAllegheny and State of Pennsylvania.

This improvement is in the means of operating the brakes of railway carsby means of atmospheric pressure obtained by producing a partial vacuum,and applied to the operative mechanism connected with the brakes. Itconsists in the use of a cylinder of thin flexible material, instead ofthe diaphragms heretofore employed; also, in connecting the heads by achain, or equivalent means, for controlling theoutward movement of theheads also, in the use of a shield for protecting the flexible material,and supporting or inclosing ways upon which the heads are supported;also, in combining, with the means for producing a partial vacuum,carried upon the locomotive,

and operated by the engineer, a pump to be located on the rear car ofthe train, and operated from the axle or by hand to exhaust the air andapply the brakes to the wheels of such cars as may become detached;also, in combining, with mechanism for operating the brakes, new andimproved means of exhausting the air also, in combination of parts to behereinafter specifically indicated in the specification and claims.

In the annexed drawing, Figure 1 is a side elevation of a locomotive andtender having the brake mechanism attached. Fig. 2 is a bot tom view ofa car with brake mechanism at tached. Fig. 3 is a transverse section ofthe shield, showing the cylinder-heads. Fig. 4 is an elevation, showingone mode of operating the brakes. Fig. 5 is a longitudinal section ofavacuum-chamberformed bytwo metallic cups. Fig. 6 is a section of theshield, showing, also, ways attached to standards instead of to theshield, as in Fig. 3. Fig. 7 is a sectional elevation, showing the modeof constructing the ways. Fig. 8 is a longitudinal section of animproved device for exhausting the air. Fig. 9 is a similar section of afurther improvement therein; and Fig. 10 is an elevation of the rearcars of the train, the sides of one being broken away to show themechanism for applying the brakes independently of the engineer.

The same letters are employed in all the figures in the designation ofidentical parts.

In the patent of Nehemiah Hodge, of 1860,

B rest.

he proposed to use a bellows-formed chamber made of leather or otherequivalent material for operating his brakes by exhausting the airtherefrom, the contraction of the chamber causing the casing to fold atthe angles formed therein. Instead of this comparatively expensivestructure, I propose to connect the iron heads B by means of a cylinderof flexible material, B forming the vacuum-chamber B for operating thebrakes A. The heads are carried on the friction-wheels B and the chamberis iuclosed in a shield, 0, on the inside of which are ways 0 on whichthe friction-wheels Instead of having the ways attached to the shield,rods 0 as shown in Figs. 6 and 7, may be fastened to standards orhangers bolted to the bottom of the car within the shield, and thefriction-wheels B placed between them. A chain, B connects the heads andprevents their being drawn apart so as to strain the easin g B by thetension of the springs of the brakes A. Instead of the chain, stops maybe placed outside of the heads to limit their outward motion; but Iprefer the chain, as it will keep open the connection between the endsof the chamber and prevent the entire collapsing of the flexiblecylinder B A pipe, D, extends from the locomotive under all the cars ofthe train, being coupled by flexible connections, and fitted with valvesto close automatically, when the cars are disconnected, so as to out offcommunication from both ends of the cars thus separated with the openair. As devices for this purpose are well known and are, some of them,in common use, they need not be here in described. This pipe or systemof connected pipes communicates with the chambers B.

The air may be exhausted through the pipe D by means of an air-pump onthelocomotive; or the cylinder of the locomotive may be made to do dutyas an air-pump when the steam is shut off; or an exhaust-jet, operatingon the principle of a Geffard injector, may be employed alone or inconnection with another form of air-pump.

I have shown, in Figs. 8 and 9, an improved form of steam-exhaust whichI prefer to use for this purpose. In this apparatus E is acylindricalcasing, formed substantially as shown, into which the steamis introduced through a pipe, E The air is exhausted through the pipe EThe force of the jet is regulated by a conical plug, E operated by aset-screw, determining its relations to the conical nozzle of thesteam-induction pipe E This mode of regulation is not new; but in theinjectors heretofore in use the plughasbeen advanced against a taperingnozzle to shut off the steam. This form of eduction-opening concentratesthe current of steam in the center of. the eductionpipe of the injector;whereas mine, by giving the hollow conical jet of steam a divergentdirection, drives it across the current of air, and consequently hastensits condensation and the consequent efficiency of the apparatus. In thelower semi-diameter of the injector I place a partition, E, which,catching the water of condensation, prevents its flowingbackinto theinduction-pipe E thereby performin g the function of the check-valvesheretofore employed. I also prefer to use the double injector shown inFig. 9,*one being larger than the other, and so constructed that, whilethe larger one will more rapidly exhaust the air, the smaller, withgreater power or intensity but less capacity, will carry on the work ofexhaustion when the larger one would no longer draw out the air, therebyproducing a more perfect vacuum, but at the same time securing rapidityof action at the commencement of the work of exhaustion.

In the pneumatic brakes heretofore used or known no provision has beenmade for applying brakes to cars which may become separated from thetrain, and consequently the trains are furnished with hand-brakes and afull complement of brakesmen to provide against accidents. I propose toput in the coupling-hose double valves or sets of valves, so that whenthe connection is broken both ends of the pipes shall be automaticallyclosed. In the rear car I place a rotary pump, L, to be operated by handor from a pulley on an axle, by means of which the air can be exhaustedfrom the brakecylinders, and the brakes applied independently of theconnection with the locomotive. A bell-cord may be carried from thelocomotive to the lever of a belt-tightener on the drivingbelt of theauxiliary pump, so that the brake may be set by the engineer, orautomatically when the bell-cord is broken on the separation of thecars. Rotary air-pumps K, driven by rotary steam-pumps, taking steamfrom the locomotive, placed side by side on one shaft, may also be usedfor exhausting the air from the vacuum-chambers.

What I claim as my invention, and desire to secure by Letters Patent,is-- 1. In combination with the car-brake, a vacuum-chamber formed bysolid heads connected by a cylindrical tube of impervious material,substantially as described.

2. In combination with the solid heads of a flexible vacuum-chamber,chains or stops for controlling the outward movement of the heads,substantially as set forth.

3. In combination with the heads of the vacuum-chamber and thecylindrical and tubular casin g B, the chain 13 for maintaining thecommunication between the ends of the chamber, substantially as setforth.

4. In combination with the flexible vacuumcylinder, the shield O,supporting or inclosin g guides 0 substantially as set forth.

5. In combination with the brakes and vacuum-chamber, double steamexhausts E E of different capacity, substantially as and for the purposeset forth.

6. In combination with the shell and induc tion air and steam pipes ofthe injector, the conical plug E arranged in relation to the flaringnozzle of the steam-induction pipe E substantially as set forth.

7. In combination with air-exhaustin g apparatus carried upon thelocomotive, and vacuumchambers, a supplemental air-pump, L, carried onthe train, and valves for closing the pipes on the rear and front endsof the cars, which are separated when the train is broken apart,substantially as set forth.

8. In combination with the air-pump and tightener M, a cord forautomatically acting on the latter when the train is broken,substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN Y. SMITH.

Witnesses:

T. G. OoNNoLLY, B10111). COVINGION.

